Related papers: Transition radiation from electrons with orbital a…
Electromagnetic radiation can be emitted not only by particle charges but also by magnetic moments and higher electric and magnetic multipoles. However experimental proofs of this fundamental fact are extremely scarce. In particular, the…
Vortex electrons, - freely propagating electrons whose wavefunction has helical wavefronts, - could become a novel tool in the physics of electromagnetic radiation. They carry a non-zero intrinsic orbital angular momentum (OAM) $\ell$ with…
While spin polarization from synchrotron radiation is well established, the polarization of orbital angular momentum (OAM) in such radiative processes remains elusive. We study radiation and polarization of relativistic electrons in a…
We explore the process of orbital angular momentum (OAM) transfer from a twisted light beam to an electron in atomic ionization within the first Born approximation. The characteristics of the ejected electron are studied regardless of the…
Following the very recent experimental realisation of electron vortices, we consider their interaction with matter, in particular the transfer of orbital angular momentum in the context of electron energy loss spectroscopy, and the recently…
The prevailing notion is that the orbital angular momentum (OAM) of an optical vortex can only be transferred to the internal degrees of freedom (i.e. electronic motion) of materials through electric quadrupole and higher-order multipole…
Twisted light beams, or optical vortices, have been used to drive the circular motion of microscopic particles in optical tweezers and have been shown to generate vortices in quantum gases. Recent studies have established that electric…
Orbital angular momentum and torque transfer play central roles in a wide range of magnetic textures and devices including skyrmions and spin-torque electronics(1-4). Analogous topological structures are now also being explored in…
Twisted photons carrying orbital angular momentum, which have potential applications spanning diverse fields, have been extensively studied since the theoretical work of Allen \textit{et al}. in 1992. Various methods for direct producing…
Recent experiments involving the interaction of optical vortices with atoms in quadrupole transitions have been shown to be accompanied by the exchange of orbital angular momentum (OAM) between the electronic states of the atom and the…
Orbital angular momentum (OAM) of photons is carried upon the wave front of an optical vortex and is important in physics research due to its fundamental degree of freedom. As for the interaction with materials, the optical OAM was shown to…
We obtain an expression for the matrix element for a twisted (Laguerre-Gaussian profile) photon scattering from a hydrogen atom. We consider photons incoming with an orbital angular momentum (OAM) of $\ell \hbar$, carried by a factor of…
Electron vortex beams carry well-defined orbital angular momentum (OAM) about the propagation axis. Such beams are thus characterised by chirality features which make them potentially useful as probes of magnetic and other chiral materials.…
Photons carry one unit of angular momentum associated with their spin~\cite{Beth1936}. Structured vortex beams carry additional orbital angular momentum which can also be transferred to matter~\cite{Allen1992}. This extra twist has been…
The recent demonstration of electron vortex beams has opened up the new possibility of studying orbital angular momentum (OAM) in the interaction between electron beams and matter. To this aim, methods to analyze the OAM of an electron beam…
We study theoretically by means of quantum electrodynamics the vortex radiation of a relativistic electron in a uniform magnetic field. The exact expressions for the probability of emission of a photon with a certain angular momentum are…
Magnetic effects on free electron systems have been studied extensively in the context of spin-to-orbital angular momentum conversion. Using a quantum field theory framework, we derive a similar relationship in the non-relativistic limit…
Illumination of a two-dimensional system by a twisted light beam is considered in order to find specific effects caused by twisting. Direct interband transitions between the valence and conduction bands are supposed. The generation rates of…
The quantum processes involved in the interaction of matter with, separately, an electron vortex(EV) and an optical vortex (OV) are described, with matter modelled in terms of a neutral two particle atomic system, allowing for both the…
Magnetic skyrmions are chiral quasiparticles that show promise for future spintronic applications such as skyrmion racetrack memories and logic devices because of their topological stability, small size (typically $\sim3-500$ nm), and…